671906 has 4 divisors (see below), whose sum is σ = 1007862. Its totient is φ = 335952.

The previous prime is 671903. The next prime is 671911. The reversal of 671906 is 609176.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 625681 + 46225 = 791^2 + 215^2 .

It is not an unprimeable number, because it can be changed into a prime (671903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 167975 + ... + 167978.

2⁶⁷¹⁹⁰⁶ is an apocalyptic number.

671906 is a deficient number, since it is larger than the sum of its proper divisors (335956).

671906 is a wasteful number, since it uses less digits than its factorization.

671906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 335955.

The product of its (nonzero) digits is 2268, while the sum is 29.

The square root of 671906 is about 819.6987251424. The cubic root of 671906 is about 87.5862985319.

The spelling of 671906 in words is "six hundred seventy-one thousand, nine hundred six".